The screening program to detect abnormal hemoglobins in progress in this laboratory will be continued. Blood samples are obtained from patients in Johns Hopkins or other clinics and hospitals, and from patients refered because of unexplained hematologic disorders. Oxygen affinity and stability, as well as electrophoretic and chromatographic mobility, are measured in the screening process. When new or unusual findings are encountered, appropriate clinical, genetic and hematologic studies are performed. Oxygen Transport to tissues will be studied in patients with disorders of red cell mass, and the effect of usual therapeutic procedures will be evaluated, by direct measurements of muscle pO2, and by estimation of redox potential and capillarity in muscle, cardiac output, oxygen consumption, and estimation of mixed venous pO2. BIBLIOGRAPHIC REFERENCES: Charache, S., Zinkham, W.H., Dickerman, J.D., Brimhall, B. and Dover, G.J.: Hemoglobin SC, SS/GPhiladelphia, and SOArab disease: Diagnostic importance of an integrative analysis of clinical, hematologic and electrophoretic findings. Amer. J. Med. 62:439-445, 1977. Charache, S., Hathaway, P., Fox, J., McCurdy, P. and Kazazian, H.: Post-synthetic deamidation of hemoglobin Providence (Beta 82 Lys - Asn, Asp), and its effect on oxygen transport. J. Clin. Invest. 59: 652-658, 1977.